The present invention relates generally to medical devices. More particularly, this invention provides a hemostatic device used to seal percutaneous blood vessel punctures or incisions.
A wide variety of medical procedures are currently performed intravascularly. Such procedures commonly involve the insertion of various medical instruments, such as catheters, into an artery. For example, in the treatment of vascular disease, balloon catheters and the like have traditionally been inserted into an artery to perform procedures therein. To facilitate such procedures, a percutaneous puncture is generally formed in the affected artery or at a peripheral location (e.g., in the femoral artery).
Commonly, an introducer sheath is inserted into the artery first. Thereafter, the medical instrument itself is inserted through the sheath and is advanced to the affected portion of the artery. After the procedure has been completed, the instrument and sheath must be withdrawn from the artery. At this stage, bleeding through the percutaneous puncture must be stopped.
Traditional methods for closing the puncture commonly involve sutures and/or the application of prolonged manual pressure to the puncture site. For example, a physician or assistant might apply digital pressure over the puncture site until hemostasis has occurred and bleeding is stopped. This can be inconvenient, as it customarily takes a considerable amount of time before the puncture is effectively closed. While pressure must commonly be applied for at least half an hour, it frequently takes much longer. Further, the application of pressure can reduce the flow of blood through the affected artery, which can cause further complications. Finally, this method can result in less than ideal wound closures which can unexpectedly reopen long after closure is apparently complete. Accordingly, patients are typically restricted to bed rest for long periods after closure, in many cases for as long as 24 hours or longer.
Attempts have been made to provide devices and methods that overcome the limitations of such traditional closure methods. For example, Kensey""s U.S. Pat. Nos. 4,744,364, 4,852,568, 4,890,612, 5,021,059, and 5,935,147 (the teachings of each of which are incorporated herein by reference) disclose similar devices and methods wherein a bioresorbable anchor is inserted through a percutaneous puncture in an artery. A tubular member containing the anchor is inserted through the opening in the artery so the distal end of the tubular member extends into the artery. The expandable anchor is then ejected into the artery through an opening in the distal end of the tubular member. A filament attached to the anchor is then pulled generally away from the artery until the anchor is pulled against the inside wall of the artery. A collagen sponge is then delivered to the puncture track, whereafter the wound is sutured closed. Thus, once the anchor member is deployed in the artery, it is never removed. Such a method seems less than ideal. For example, if the anchor is not properly deployed in the artery, then it may obstruct blood flow through the artery, compromising vessel patency. It would be more desirable to provide a vascular closure method where nothing remains in the artery after wound closure.
Several researchers have proposed methods and devices to achieve that end. U.S. Pat. Nos. 5,868,778 and 5,957,952 (both issued to Gershony et al.), and U.S. Pat. No. 5,951,583, (issued to Jensen et al.), disclose similar methods and devices for sealing percutaneous punctures using a balloon catheter. These references involve the insertion of the catheter into the artery until the balloon near the distal end of the catheter is positioned within the bloodstream. The balloon is then expanded and pulled against the interior wall of the artery at the puncture site, thereby temporarily closing the puncture. A liquid procoagulant is then introduced into the tissue track that extends through the tissue overlying the artery. Once hemostasis occurs, the balloon is deflated and the entire device is withdrawn from the artery. Unfortunately, there appears to be an appreciable risk that the balloon may rupture. This could leak procoagulant into the bloodstream, which could result in blood clotting and vascular occlusion in the patient""s circulatory system.
U.S. Pat. Nos. 5,391,183; 5,591,204; 5,725,498; and 5,948,425, all issued to Janzen et al., and U.S. Pat. Nos. 5,853,421 and 5,728,122, issued to Leschinsky et al., suggest sealing arterial punctures by applying a plug of hemostatic material to the outside wall of a punctured artery. In the first step of one described method, the distance between the skin and artery is measured. A dilator and sheath may then be advanced to the measured depth. Alternatively, they may be advanced until they press upon the artery wall (whereupon increased resistance is felt). A collagen plug is then advanced toward the artery until it abuts the outer wall of the artery and overlaps the puncture on all sides. If the depth of the vascular track has not been properly measured, then over-deployed collagen might be dislodged to blood stream. This could result in blood clotting and vascular occlusion in the patient""s circulatory system. The latest version of the device uses a J-locator to determine the tissue depth, which eliminates the need for a measurement. Still, the procedure seems complicated.
The present invention provides a vascular sealing device and a sealant for closing a puncture, incision, or other opening in the wall of a blood vessel. The invention also includes a method for closing such openings.
One embodiment of the present invention provides a vascular sealing device. The device includes a sheath that can be positioned so a distal end thereof is adjacent the opening. A solid mandrel is disposed within a lumen of the sheath. A collapsible sealing member having a fluid-impervious film carried by a plurality of wires is attached to the mandrel.
In another aspect of this invention, sealant is introduced to an area adjacent an opening in a blood vessel. The sealant may be introduced by flowing it into position. The sealant may be syringe injected. Alternatively, the sealant may be introduced by delivering it from a tampon. The sealant introduced may be a procoagulant. A thermally reversible material may be used as the sealant. The sealant may alternatively be a photo-initiated material. A second material may be brought into contact with the sealant to cause an in situ crosslink reaction, whereby the sealant and the second material begin to solidify.
In accordance with yet another embodiment, the present invention provides a method for closing an opening in a blood vessel of a patient. The method comprises providing a collapsible sealing member mounted on a mandrel. The sealing member has a naturally expanded configuration. A sheath with a distal end adjacent the opening in the blood vessel is also provided. The sheath has a lumen that is smaller than the expanded sealing member so the sealing member is kept in a collapsed position when it is inside the sheath. The sealing member is advanced through the sheath and beyond to its distal end, whereby it resiliently expands. The sealing member is then positioned against the inner wall of the blood vessel adjacent the opening to affect a temporary seal of the opening. A procoagulant is then introduced to an area adjacent the opening. Finally, the sealing member is collapsed within the sheath and withdrawn from the patient along with the sheath.